Abstract:Based on the differences of rRNA intergenic sequences between wheat ( Triticum aestivum L. ) and rye ( Secale cereale L. ), rye specific primer set NOR-R1 was synthesized according to Koebner‘ design. PCR analyses were carried out on different DNA substrates of common wheat and its relatives such as Agropyron elongataum (Host) Beauv., Haynaldia villosa Shur. and Hordeum vulgare L. The results confirmed that NOR-R1 primer set is specific to rye. It was found that PCR using DNAs from wheat materials containing 1R chromosome resulted in the specific amplification products of rye, whereas no amplification product was detected in PCR when using DNAs with other rye chromosomes. FISH (Fluorescent in situ Hybridization) further revealed that the binding sites for the primer set NOR-R1 were only on nucleolar organizing region of chromosome 1R. These results indicated that the primer set NOR-R1 provides a useful means for molecular tagging of rye chromosomes 1 R in wheat genetic background.